ARRL Propagation Bulletin ARLP024 (2000)

SB PROP @ ARL $ARLP024
ARLP024 Propagation de K7VVV
ZCZC AP24
QST de W1AW
Propagation Forecast Bulletin 24 ARLP024
From Tad Cook, K7VVV
Seattle, WA June 16, 2000
To all radio amateurs
SB PROP ARL ARLP024
ARLP024 Propagation de K7VVV
Solar and geomagnetic activity rose this week. Average sunspot
number was up nearly 84 points and solar flux was up by over 13
points compared with last week. Average planetary A index was nearly
double. Solar flux probably peaked at 1700z on Wednesday at 205.5.
The official solar flux for that day was taken at 2000z and was
200.6.
Solar flux for the near term is expected to fall, with the values
for Friday through Tuesday at 200, 195, 190, 185 and 180. Flux
values should bottom out around 150 from June 27 through 29, and
then peak again around July 12.
For the All Asia DX CW Contest this weekend expect good conditions,
barring some unexpected flare and geomagnetic disturbance.
Sometimes unexpected flares disrupt communication, and other times
expected events do not happen. An example of this was the past
weekend, when energy from a mass ejection on June 10 bypassed the
earth around 2200z on June 12.
AA1LL wrote to say that his web site at http://www.qsl.net/aa1ll/
shows a graph of predicted solar flux and A index from the weekly 27
day outlook from NOAA. Check it out.
Sunspot numbers for June 8 through 14 were 203, 183, 165, 224, 236,
243 and 278 with a mean of 218.9. 10.7 cm flux was 174.6, 168.9,
179.6, 186.8, 192.7, 199.2 and 200.6, with a mean of 186.1, and
estimated planetary A indices were 53, 8, 25, 32, 15, 16 and 23,
with a mean of 24.6.
NNNN
/EX